The Bearing Capacity of Compressed Corrosion-Damaged Reinforced Concrete Elements under Lateral Pulse Loading

Abstract

This article addresses the relevant problem of the stress–strain behavior of compressed reinforced concrete columns under lateral pulse loading. A simplified engineering method of analyzing the limit value of lateral pulse loading P, depending on longitudinal force N acting on the column, is developed. The proposed method involves the construction of the P-N curve that has three portions. Portion 1 describes the plastic deformation of concrete and rebars of that part of the structure that is mostly in bending. Portion 2 describes the state of the column that can trigger the brittle failure of the concrete along the normal section, and Portion 3 describes the high compression of the column that predominantly triggers its shear failure. For Portions 1 and 2, analytical relationships are obtained using equilibrium equations. Corrosive damage is taken into account in the analytical model as a reduction in the strength and deformability characteristics of the material. A conventional local corrosion spot can be considered; it can be located both in and outside of the area of action of lateral pulse loading. The results obtained using the proposed model were compared with the results of numerical studies and a full-scale experiment. As a result of testing the developed engineering technique, it was found that it provides a safety margin for corrosion-damaged elements of 0.20–0.8 of the ultimate value of horizontal impulse at operational values of compressive force. The spot corrosion damage considered in the paper leads to a 10–60% strength reduction in compressed columns, depending on their location.